The bootstrap_server_addresses configuration option is deprecated in favor of the new dynamic_config option. (Bug #28082857, Bug #91029, WL #11318)

A new dynamic configuration bootstrap feature was added that tracks the current MySQL InnoDB Cluster Metadata servers. This replaces the existing bootstrap_server_addresses option with the new dynamic_config option in mysqlrouter.conf.

MySQL Router now tracks and stores active MySQL InnoDB Cluster Metadata server addresses and loads them if Router is restarted. Previously, metadata server information was defined during Router's initial bootstrap operation and stored statically as bootstrap_server_addresses in the configuration file.

This new dynamic_config option is generated by --bootstrap and is defined under mysqlrouter.conf's [DEFAULT] section. Its value points to a generated JSON file named state.json that's initialized with InnoDB Cluster Metadata server addresses and the group replication ID; and additional information is added and updated while Router is running.

The bootstrap process no longer defines bootstrap_server_addresses because dynamic_config replaces its functionality; and these two options cannot be set at the same time. For backwards compatibility, if only bootstrap_server_addresses is set then it functions as it did in previous Router versions and this new dynamic configuration functionality is not used. (Bug #28082857, Bug #27015184, Bug #91029, WL #11318)

MySQL Router now persistently tracks the metadata server addresses rather than only using the static list defined in the configuration file using the destinations option. (WL #11318)

The standalone MySQL Router zip file did not include its own copy of the OpenSSL libraries, so the Router binary would not start unless the MySQL Server zip file was also installed on the host. (Bug #29132062)

The copyright years in the README and LICENSE files were not synced. (Bug #29045945)

The --version output was aligned with MySQL Server's layout. (Bug #28899194)

Router would unexpectedly halt upon receiving an unexpected packet; now an exception is thrown. (Bug #28793334)

Solaris MySQL Router packages would not function with MySQL Server 8.0.13 due to an incorrect CMake rpath value. (Bug #28730189)

Linking Router against libmsyqlclient that was built with DBUG enabled led to slow Router shutdown procedures. (Bug #28656618)

Fixed a thread shutdown race condition. (Bug #28610484)

Sending mysqlrouter a SIGTERM would take at least 100ms to shut down. Now a concurrent plugin shutdown queue was added to speed up the shutdown process. (Bug #28570122)

A metadata-cache API method was added to check the initialization status. Routing plugins use this during initialization to safely register the callbacks after metadata-cache is initialized. (Bug #28569717)

Installing MySQL Server with Router from source or building a tarball with "make package" would create a top level "data/" directory as part of the "Router" component. Due to possible collisions with MySQL Server, "data/" was changed to "var/lib/mysqlrouter". (Bug #28537733)

The connection error counter that blocks clients after max_connect_errors connection errors did not reset after a successful connection. (Bug #27995042, Bug #90809)

The MySQL metadata server's connect_timeout default value changed from 30 to 15 seconds. (Bug #27326466)